Devices and methods for treatment of body lumens

ABSTRACT

A method for performing a medical procedure may comprise advancing a first device through a first body lumen. A distal portion of the first device may include a magnet. The method may further comprise advancing a second device through a second body lumen. The second device may include a magnetic field sensor. The method may further comprise_receiving a signal from the magnetic field sensor. The signal may be indicative of a magnetic field measured by the magnetic field sensor. The method may further comprise, if the received signal matches a magnetic field of the magnet, identifying a position of the magnet.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from U.S. ProvisionalApplication No. 62/752,574, filed on Oct. 30, 2018, which isincorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to devices and methods fordiagnosing and/or treating tissue using, for example, endoscopes,bronchoscopes, and ureteroscopes. More specifically, aspects of thepresent disclosure pertain to devices and methods for positioningmedical devices within body lumens of a subject.

BACKGROUND

Endoscopic, bronchoscopic, or ureteroscopic techniques may be used fordiagnosing, treating, and/or monitoring conditions by advancing toolsand other devices through body lumens. Such techniques may providetreatment options without a need for making incisions in a patient'sskin. However, endoscopic devices may be limited in their ability toperform certain procedures due to, for example, difficulties invisualizing areas of interests.

Difficulties may arise, for example, in procedures that involve multiplebody lumens or that involve portions of a single lumen separated bytissue walls. For example, in gastric bypass procedures, a portion of astomach lumen may be connected to a portion of an intestinal lumen suchas the jejunum. It may be desirable to create an anastomosis between aparticular portion of the jejunum and the stomach. Typical therapeuticand diagnostic endoscopes may be limited in their ability to identify anappropriate portion of the intestine which should be connected to thepouch or other portion of the stomach. For example, an ultrasonicendoscope may have a range that is too small in order to effectivelyidentify the relevant portion of the intestine. For example, anendoscope may be unable to reach the target location and/or theultrasound may have a range that is unable to visualize (e.g., through awall of a body lumen) a target location because it is too far away fromthe ultrasound.

SUMMARY

Examples of the present disclosure relate to, among other things,devices and methods for identifying and/or detecting portions of a bodylumen of a subject. Each of the examples disclosed herein may includeone or more of the features described in connection with any of theother disclosed examples.

In one example, a method for performing a medical procedure may compriseadvancing a first device through a first body lumen. A distal portion ofthe first device may include a magnet. The method may further compriseadvancing a second device through a second body lumen. The second devicemay include a magnetic field sensor. The method may furthercomprise_receiving a signal from the magnetic field sensor. The signalmay be indicative of a magnetic field measured by the magnetic fieldsensor. The method may further comprise, if the received signal matchesa magnetic field of the magnet, identifying a position of the magnet.

Any method described herein may include one or more of the features orsteps described below. The method may further comprise identifying alocation of a tissue wall surrounding the first body lumen. The locationmay be proximate to the magnet. The first body lumen may be a smallbowel lumen. The second body lumen may be a stomach lumen. The methodmay further comprise joining the first lumen to the second lumen. Thesignal may include information regarding at least one of a direction ora magnitude of the magnetic field. The magnet may be a diametricalmagnet. The first device may include at least one magnetically shieldedportion. The second device may further include an atraumatic grasper.The distal portion of the first device may further include a lightemitting source. The method may further comprise detecting a lightemitted by the light emitting source. The method may further compriseforming a first hole in a first tissue wall defining the first bodylumen. The method may further comprise forming a second hole in a secondtissue wall defining the second body lumen. The method may furthercomprise joining the first tissue wall to the second tissue wall. Afterthe first tissue wall and the second tissue wall are joined, the firsthole may be in communication with the second hole. The magnetic fieldmay have a direction perpendicular to a tissue wall defining the firstbody lumen.

In another example, a method for performing a medical procedure maycomprise: advancing a first device through a first body lumen to aportion of the first body lumen. A distal portion of the first devicemay include a magnet. The method may further comprise advancing a seconddevice through a second body lumen. The second device may include amagnetic field sensor. The method may further include receiving a signalfrom the magnetic field sensor. The signal may be indicative of amagnetic field measured by the magnetic field sensor. Based on thereceived signal, the portion of the first body lumen may be joined tothe second body lumen.

Any method described herein may include one or more of the features orsteps described below. The method may further comprise identifying alocation of a tissue wall surrounding the first body lumen. The locationmay be proximate to the magnet. The first body lumen may be a smallbowel lumen. The second body lumen may be a stomach lumen. The methodmay further comprise grasping a wall surrounding the first body lumenproximate to the portion of the first body lumen. The magnetic field mayhave a direction perpendicular to a tissue wall defining the first bodylumen.

In a still further example, a method for performing a medical proceduremay comprise: advancing a first device through a first body lumen. Adistal portion of the first device may include a magnet. The method mayfurther comprise advancing a second device through a second body lumen.The second device may include a magnetic field sensor. The method mayfurther comprise receiving a signal from the magnetic field sensor. Thesignal may be indicative of a magnetic field measured by the magneticfield sensor. Based on the received signal, a medical tool may beadvanced from the second body lumen into the first body lumen.

Any method described herein may include one or more of the features orsteps described below. The method may further comprise identifying alocation of a tissue wall surrounding the first body lumen. The locationmay be proximate to the magnet. The first body lumen may be a smallbowel lumen. The second body lumen may be a stomach lumen. The magneticfield may have a direction perpendicular to a tissue wall defining thefirst body lumen.

In another example, a system for performing a medical procedure maycomprise a first device. A distal portion of the first device mayinclude a magnet having a magnetic field. The first device may beconfigured to be advanced into a first body lumen. The system may alsocomprise a second device. The second device may include a magnetic fieldsensor. The magnetic field sensor may be configured to transmit a signalindicative of a magnetic field measured by the magnetic field sensor.The signal may be compared to one or more parameters relating to themagnetic field of the magnet, for identifying a position of the magnet.

Any system described herein may include one or more of the featuresdescribed below. The signal may include information regarding at leastone of a direction or a magnitude of the magnetic field. The magnet maybe a diametrical magnet. The first device may include at least onemagnetically shielded portion. The first device may include at least onemagnetically shielded portion proximal of the magnet and at least onemagnetically shielded portion distal of the magnet. The second devicemay further include an atraumatic grasper. The distal portion of thefirst device may further include a light emitting source. The seconddevice may include an optical device for detecting the light emittingsource. The magnetic field may have a direction perpendicular to atissue wall defining the first body lumen. The second device may beconfigured for insertion within a working channel of a sheath. The firstbody lumen may be a small bowel lumen, and the second body lumen may bea stomach lumen. The first device may include an articulation joint andhand-held controls. The identified position may be indicative of alocation of a tissue wall in which a hole is to be formed. The firstdevice may be configured to be positioned so that the magnet isapproximately 150 cm distal to a pylorus. The first device may beconfigured to be inserted into the first lumen at the same time thesecond device is inserted into the second lumen. The magnetic fieldsensor may be at least one of a Hall effect sensor, a magnetoresistivesensor, a flux gate, a flux coil, or a magnetoinductive sensor.

It may be understood that both the foregoing general description and thefollowing detailed description are exemplary and explanatory only andare not restrictive of the invention, as claimed. As used herein, theterms “comprises,” “comprising,” or any other variation thereof, areintended to cover a non-exclusive inclusion, such that a process,method, article, or apparatus that comprises a list of elements does notinclude only those elements, but may include other elements notexpressly listed or inherent to such process, method, article, orapparatus. The term “exemplary” is used in the sense of “example,”rather than “ideal.” The term “endoscope” may be used herein but is notlimiting. References to endoscopes may also include other medicaldevices, including, but not limited to, bronchoscopes, ureteroscopes,colonoscopes, catheters, sheaths, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate examples of the presentdisclosure and together with the description, serve to explain theprinciples of the disclosure.

FIG. 1 shows an exemplary system for performing a medical procedure suchas a gastroenteral anastomosis procedure.

FIG. 2 shows an exemplary distal portion of an endoscope for use with asystem for performing medical procedure such as a gastroenteralanastomosis procedure.

FIGS. 3A-3C show an exemplary magnetic component for use with a systemfor performing a gastric bypass procedure.

FIGS. 4-6 show exemplary systems for performing gastric bypassprocedures.

FIG. 7 shows a flow chart of an exemplary medical procedure.

DETAILED DESCRIPTION

The present disclosure is drawn to devices, systems, and methods fordiagnosing and/or treating tissue using, for example, endoscopes,bronchoscopes, ureteroscopes, and other medical devices. Morespecifically, aspects of the present disclosure pertain to devices andmethods for positioning medical devices within body lumens of a subject.In particular, at least in some aspects, the devices, systems, andmethods disclosed herein may facilitate identifying and/or detectingportions of a body lumen of a subject. Although gastrointestinal anatomymay be referenced herein, reference to gastrointestinal anatomy shouldnot be construed as limiting possible applications of the discloseddevices and methods. The disclosed devices and methods may be suitablefor use in a variety of portions of a subject's body, including, forexample, urological organs, the respiratory system, or other portions ofthe digestive system. And although a gastric bypass procedure may bereferenced herein, the disclosed devices and methods may be used for avariety of medical procedures, including any procedure requiring preciselocation of a position within a body lumen.

FIG. 1 depicts an exemplary system 10 for performing a gastric bypassprocedure. System 10 may include a first device 12 and a second device14. Devices 12 and/or 14 may be, for example, endoscopic devicessuitable for insertion into a body lumen of a subject. While firstdevice 12 and second device 14 are shown in FIG. 1 as stand-alonedevices (e.g., an endoscopic device) inserted directly into a body lumenof a patient, it will be understood that first device 12 and seconddevice 14 may be used in conjunction with other devices. For example,first device 12 and/or second device 14 may be inserted into a bodylumen of a patient via a sheath such as an endoscopic sheath. Forexample, a sheath could be inserted into a body lumen of a patient, andthen first device 12 and/or second device 14 could be inserted into aworking channel of the sheath.

First device 12 may be insertable into a subject and may include anelongate member or shaft 20. Member 20 may be made of a flexiblematerial that is suitable for use inside a body lumen of a subject.Member 20 may be steerable via, for example, hand-held controls externalto the body and an articulation joint at a distal end of member 20.Alternatively, member 20 may be passively bendable in a body lumen of asubject. Member 20 may have a distal portion 22. Distal portion 22 mayinclude any suitable mechanisms for visualizing and/or navigating a bodylumen of a subject. For example, distal portion 22 may include a lightedportion, a camera, or any other suitable device. Alternatively, firstdevice 12 may be configured to be inserted along with another devicethat includes mechanisms for steering and/or navigating. For example,first device 12 may be inserted in a working channel of a sheath such asa sheath of an endoscope. First device 12 may remain in a body lumen ofa subject after such an insertion device is removed from the body lumen.Alternatively, both first device 12 and an insertion device or mechanismfor navigating first device 12 may remain in a body lumen of a patient.A distal portion 22 of first device 12 may include a distal tip 24.Distal tip 24 may have atraumatic features, such as a rounded tip, inorder to avoid damage to tissues of a body lumen of a subject. Distaltip 24 may additionally or alternatively have openings for lightingand/or video mechanisms and/or openings for irrigation, suction,insufflation, or other functionality. For example, distal tip 24 mayinclude openings for one or more LEDs, cameras, lenses, optical fibers,etc.

Distal portion 22 (or another portion of first device 12) may alsoinclude a magnetic device 26. Magnetic device 26 may be a permanentmagnet or may be activated by a current running through wires of shaft20 and magnetic device 26. Magnetic device 26 may have a known magneticfield such as, for example, the magnetic field discussed below withregard to FIGS. 3A-3C. In particular, a field of magnetic device 26 maybe known in a region between magnetic device 26 and a stomach lumen of asubject, when first device 12 is inserted into a portion of a smallintestine of the subject, as shown in FIG. 1 . For example, a magneticfield in a stomach lumen in a region near a major curvature or a pylorusof a subject's stomach may be known. For example, a general shape of thefield, a general strength of the field, etc. may be known. For example,it may be known that the strongest magnetic field corresponds to aparticular location of the magnetic device 26. While exemplary magneticfields are discussed below, a variety of magnetic field configurationsmay be suitable for the devices, systems, and methods disclosed herein.

Second device 14 may be insertable into a subject and may include anelongate member 30. Member 30 may be made of a flexible material that issuitable for use inside a body lumen of a subject. Member 30 may besteerable via, for example, hand-held controls external to the body andan articulation joint at a distal end of member 30. Alternatively,elongate member may be passively bendable in a body lumen of a subject.Member 30 may have a distal portion 32. Distal portion 32 may includeany suitable mechanisms for visualizing and/or navigating a body lumenof a subject. For example, distal portion 32 may include a lightedportion, a camera, or any other suitable device. Alternatively, seconddevice 14 may be configured to be inserted along with another devicethat includes mechanisms for steering and/or navigating. For example,second device 14 may be inserted in a working channel of a sheath suchas a sheath of an endoscope. Second device 14 may remain in a body lumenof a subject after such an insertion device is removed from the bodylumen. Alternatively, both second device 14 and an insertion device ormechanism for navigating second device 14 may remain in a body lumen ofa patient. A distal portion 32 of second device 14 may include a distaltip 34. Distal tip 34 may have atraumatic features, such as a roundedtip, in order to avoid damage to tissues of a body lumen of a subject.Distal tip 34 may additionally or alternatively have openings forlighting and/or video mechanisms and/or openings for irrigation,suction, insufflation, or other functionality. For example, distal tip34 may include openings for one or more LEDs, cameras, lenses, opticalfibers, etc.

Distal portion 32 (or another portion of second device 14) may alsoinclude a magnetic field sensor 36. Magnetic field sensor 36 may be anysuitable type of magnetic field sensor known in the art, such as, forexample, a Hall effect sensor, a magnetoresistive sensor, a flux gate orcoil, or a magnetoinductive sensor. Magnetic field sensor 36 may measureone or more of a magnitude or direction of a magnetic field. The abovetypes of magnetic field sensors are merely exemplary and are notlimiting. Magnetic field sensor 36 may be any type of sensor configuredto measure a magnetic field. Magnetic field sensor 36 may measure adirection and/or magnitude of a magnetic field emitted by magneticdevice 26. Magnetic field sensor 36 may be configured to transmit asignal regarding a direction and/or a magnitude of a measured magneticfield. A controller may be configured to compare the signal to one ormore parameters relating to known features (e.g., direction or strength)of the magnetic field of the magnet, for identifying a position of themagnet. Alternatively, the signal measured by magnetic field sensor 36may be compared to one or more parameters related to the magnetic fieldof magnetic device 26, such as by manual comparison by an operator or byother means. The compared parameters may be used to identify a locationor position of magnet 26, as described herein (e.g., by use of adirection of a magnetic field of magnet 26 or a magnitude of a directionof a magnetic field of magnet 26). Magnetic field sensor 36 mayadditionally or alternatively be configured to identify when a region ofthe largest measured magnetic field has been identified.

Second device 14 may be advanced into a stomach of a subject so thatdistal portion 32, including magnetic field sensor 36, is positioned ina known or otherwise predetermined area of the stomach (e.g., near awall of the stomach proximate to the greater curvature, antrum, and/orthe pylorus). For example, distal portion 32 may be advanced to aportion of the stomach where a bypass procedure will be performed inorder to connect a pouch of the stomach to the ileum or other portion ofthe small intestine.

First device 12 may be advanced though a subject's small intestine untila known or otherwise predetermined portion of the small intestine isreached. For example, it may be desirable to perform a gastric bypassbetween the stomach and a portion of the small intestine approximately150 cm past the pylorus. First device 12 may include markings or otherfeatures which enable a user to advance first device 12 to a knownposition (e.g., approximately 150 cm past the pylorus). For example,hash markings or ruler-type markings may be used on a portion of firstdevice 12 such as an outer jacket or catheter so that, after the markedportion of device 12 reaches the end of an endoscope used for insertionof device 12, the markings can be used to measure how far device 12extends into the jejunum. Additionally or alternatively, a shaft offirst device 12 may change color at a distance of 150 cm so that thedistance of the pylorus is obvious by looking at the color of a shaft offirst device 12 at the pylorus.

Second device 14 may then be maneuvered in a stomach lumen untilmagnetic field sensor 36 obtains a reading indicative that magneticfield sensor 36 is adjacent to magnetic device 26. In this way, it maybe determined that magnetic field sensor 36 is adjacent to magneticdevice 26, despite the fact that two tissue walls (e.g., a wall of thestomach and a wall of the ileum) may be in between magnetic field sensor36 and magnetic device 26. Additionally or alternatively, second device14 may be moved relative to first device 12, and attributes of amagnetic field may be measured by magnetic field sensor 36. Astrengthening magnetic field may be indicative that magnetic fieldsensor 36 is growing nearer to magnetic device 26 along any relevantdimension. For example, if a magnetic field of magnetic device 26 isconfigured to be detectable in a direction substantially perpendicularto magnetic device 26 (for example, because portions of the fieldemitting in other directions are shielded, as discussed herein), ameasured magnetic field may increase in strength (either gradually orsharply) when magnetic field sensor 36 is proximate to magnetic device26. For example, an area of the strongest measured magnetic field may bean area that is closest to magnetic device 26. Further details ofmethods for using first device 12 in conjunction with second device 14will be discussed below.

FIG. 2 depicts further details of a distal portion 22 of first device12. As shown in FIG. 2 , and discussed above, distal portion 22 may havea distal tip 24 and a magnetic device 26. Magnetic device 26 may be apermanent magnet or an electromagnet. The two poles of magnetic device26 may be oriented in any suitable manner. For example, magnetic device26, as shown in FIG. 2 , may be a diametric magnet. Magnetic device 26may have a round perimeter, and the poles, 40 and 42, of magnetic devicemay be located on opposite sides of a diameter of magnetic device 26.For example, magnetic device 26 may include a first pole 40 thatoccupies an area of magnetic device 26 on one side of a diameter ofmagnetic device 20. First pole 40 may be, for example, a north pole ofmagnetic device 26. Magnetic device 26 may also include a second pole 42that occupies an area of magnetic device 26 on the other side of adiameter of magnetic device 26 opposite of first pole 40. Second pole 42may be, for example, a south pole of magnetic device 26. Alternatively,magnetic device 26 may be round but may have poles aligned along aradius of magnetic device 26 (e.g., an inner portion of magnetic device26 may have one pole, where an outer portion of magnetic device 26 mayhave another pole) or may have poles divided along a height of magneticdevice 26 (e.g., a magnetic device 26 may be split in half along aheight of magnetic device 26 so that each pole has a circular,cylindrical, disk-like shape). Alternatively, magnetic device 26 mayhave other shapes and configurations of poles. For example, magneticdevice 26 may be cylindrical, washer-shaped, polygonal, pyramid-shaped,cone-shaped, or prism-shaped.

A portion of shaft 20 of first device 12 that is proximal of magneticdevice 26 may include a magnetic shielding. Magnetically shieldedportion 44 may extend proximally from a position 0.5 cm-1 cm proximal ofmagnetic device 26. Magnetically shielded portion 44 may extendproximally to an operation portion (e.g., a handle or actuator) that isproximal to shaft 20. Alternatively, magnetically shielded portion 44may extend proximally only partially along shaft 20. For example,magnetically shielded portion 44 may extend to a portion of shaft 20where the effects of magnetic device 26 may no longer be substantiallyfelt. Magnetically shielded portion 44 may include a coating on asurface of shaft 20. Magnetically shielded portion 44 may include, forexample, a film coated on shaft 20. Alternatively, magnetically shieldedportion 44 may be a portion of shaft 20 that is formed from a differentmaterial than other portions of shaft 20. Any suitable material may beused to form magnetically shielded portion 44. For example, magneticallyshielded portion 44 may be formed from a metallic thin film including,for example, nickel, aluminum, or other metallic materials that offermagnetic shielding. Additionally or alternatively, a small disk couldform a shield and may be made of any of the materials above.

A distalmost portion of shaft 20, proximal to distal tip 24, may alsoinclude a magnetically shielded portion 46. Magnetically shieldedportion 46 may have any of the properties of magnetically shieldedportion 44, as discussed above. Magnetically shielded portion 46 mayextend from distal tip 24 to a portion of shaft 20 that is apredetermined distance distal of magnetic device 26 (such as 0.5 cm-1 cmfrom magnetic device 26). Alternatively, magnetically shielded portion46 may not extend all the way to a distal tip 24. Magnetically shieldedportion 46 may extend far enough distally to where a field of magneticdevice 26 does not extend.

An unshielded portion 48 may be proximate to magnetic device 26.Unshielded portion 48 of device 12 may extend approximately onecentimeter each of proximally and distally from magnetic device 26 ormay extend for approximately one centimeter in total length, straddlingmagnetic device 26. The shielding may serve to concentrate the magneticfield of magnetic device 26 in the examples herein. Alternatively,unshielded portion 48 may extend any suitable distance proximally and/ordistally from magnetic device 26. Unshielded portion 48 may extend anequidistance in a proximal and distal direction relative to magneticdevice 26. Alternatively, unshielded portion 48 may be asymmetricalrelative to magnetic device 26. For example, unshielded portion 48 mayextend further proximally or further distally relative to magneticdevice 26.

Magnetically shielded portions 44 and 46 may block or divert passage ofa magnetic field emitted by magnetic device 26 so that a magnetic fieldmay not pass through a wall of member 20 where magnetically shieldedportions 44 and 46 are present. In contrast, unshielded portion 48 mayallow a magnetic field emitted by magnetic device 26 to pass through thewalls of member 20 in the location of unshielded portion 48. A presenceof magnetically shielded portions 44 and 46 may cause a magnetic fieldemitted by magnetic device 26 to take on a more focused shape. Forexample, in the region of unshielded portion 48, a magnetic fieldemitted by magnetic device 26 may be mostly or substantiallyperpendicular relative to a longitudinal axis of member 20. Shieldedportions 44 and 46 may block passage of a magnetic field from magneticportion 26 where the magnetic field would be relatively lessperpendicular relative to a longitudinal axis of the member 22.

FIGS. 3A-3C show further details regarding a magnetic device 26. FIGS.3A-3C show magnetic device 26 as a diametric magnet. However, asdescribed above, magnetic device 26 may have any suitable shape orconfiguration. For example, magnetic device 26 may be an electromagnetthat produces the same magnetic field as a diametric magnet. FIGS. 3A-3Cshow exemplary magnetic field lines of magnetic device 26. FIG. 3A showsa perspective view of magnetic device 26, FIG. 3B shows a side view ofmagnetic device 26, and FIG. 3B shows a top view of magnetic device 26.Magnetic field lines shown in FIGS. 3A-3C are merely schematic and donot portray the precise or specific magnetic field of magnetic device26. Rather, they are merely exemplary and representative of a generalcharacter of possible magnetic field lines of magnetic device 26. Asshown in FIGS. 3A-3C, magnetic field lines representing a magnetic fieldof magnetic device 26 may extend from pole 40 of magnetic device 26 topole 42 of magnetic device 26. Pole 40 may be a north pole of magneticdevice 26, and pole 42 may be a south pole of magnetic device 26. If,instead, pole 40 were a south pole and pole 42 were a north pole, then adirection of the illustrated magnetic field lines may be reversed.

FIG. 4 shows an interaction between a magnetic device 26 and a magneticfield sensor 36 when first and second devices 12 and 14 are insertedinto body lumens. In an exemplary procedure, first device 12 may beinserted into an intestinal lumen of a subject. For example, a distalportion 22 of first device 12 may be inserted into a mouth of a subject,through an esophagus, through a stomach, and into a small intestine ofthe subject. First device 12 may include features such as those known inthe art for advancing distal end 22 of first device 12 into a knownlocation of a small intestine, such as the jejunum or the ileum. Forexample, distal end 22 of first device 12 may be inserted approximately150 centimeters into a small intestine of a subject. Second device 14may simultaneously, previously, or subsequently be inserted into astomach lumen of the subject. A distal portion 32 of second device 14may be inserted into a mouth of a subject and down the subject'sesophagus, into the subject's stomach. Second device 14 may be advanceddistally into the stomach.

Magnetic field sensor 36 may be used while second device 14 is navigatedin a subject's stomach lumen. Distal portion 22 of first device 12,including magnetic device 26, may be held in place at a desired locationin the small intestine lumen (e.g., 150 cm into the small intestine). Anoperator may receive from magnetic field sensor 36 a signal indicativeof a magnetic field measured by magnetic field sensor 36. An operator ofsecond device 14 may analyze a signal or other output from magneticfield sensor 36, looking for a signature of magnetic device 26. When asignature of magnetic device is received (e.g., by a magnetic fieldpointing perpendicular to a tissue wall surrounding an intestinal and/orstomach lumen, for a magnetic device 26 as depicted in FIGS. 3A-3C),then an operator may know that magnetic field sensor 36 is positioned ina portion of the stomach lumen adjacent to or proximate to a desiredlocation in the small intestine (e.g., 150 cm into the small intestine).An operator may be able to identify a tissue wall surrounding the secondlumen that is proximate to and/or adjacent to a position in the firstlumen where magnetic device 26 is located. System 10 may facilitate anoperator in grasping or otherwise manipulating a tissue wall surroundingthe first lumen and proximate to the magnetic device 26. For example,when a magnetic device is advanced 150 cm into a small intestine pastthe pylorus, an operator may be able to identify a portion of a stomachwall that is proximate to or adjacent to a wall of a small intestinethat is 150 cm past the pylorus. The same principles apply to other bodylumens and/or other locations within body lumens.

Following recognition by magnetic field sensor 36 of an appropriatesignature of a magnetic field of magnetic device 26, an operator mayproceed to perform a procedure involving the identified tissue portion.A medical tool may be advanced into the second lumen from the firstlumen. A portion of a tissue wall defining the first lumen may be joinedto a portion of a tissue wall defining the second lumen via, forexample, a perforation in a wall surrounding the second lumen. Theperforation may be made proximate to the magnetic device 26. Forexample, a first hole may be formed in the tissue wall defining thefirst lumen, and a second hole may be formed in the tissue wall definingthe second lumen. The tissue wall defining the first lumen may be joinedto the tissue wall defining the second lumen so that the first hole andthe second hole are in communication with another. A continuous lumenmay be formed between the first lumen and the second lumen via the firsthole and the second hole. For example, an operator may perform a gastricbypass procedure by forming a passage between a stomach and anidentified portion of a patient's small intestine. A portion of apatient's stomach lumen may be joined to a portion of the intestinallumen. Food may bypass portions of the intestinal lumen proximal to thecreated junction between the stomach lumen and the intestinal lumen.Food may pass through portions of the intestinal lumen distal to thecreated junction between the stomach lumen and the intestinal lumen. Forexample, food may pass through portions of the intestinal lumen greaterthan 150 cm from the pylorus.

FIG. 5 shows an alternative system 100, which makes use of analternative second device 102. Second device 102 may have any of theproperties of second device 14, discussed above. Second device 102 mayinclude an elongate member 104, which may have any of the properties ofmember 30, discussed above. Member 104 may have a distal portion 106,which may have any of the properties of distal portion 32. Second device102 may also include a tool 108. Tool 108 may be any suitable form oftool that may be, for example, inserted in a working lumen of member 104or otherwise included with member 104. Member 104 may have one or moreworking lumens. For example, member 104 may have a 3.8 mm working lumenand a 2.8 mm working lumen. Tool 108 may be passed through a workinglumen of member 104, such as a 2.8 mm working lumen of member 104. Forexample, tool 108 may be an atraumatic small bowel grasper or any othertype of tool.

Tool 108 may include a magnetic field sensor 110. Magnetic field sensor110 may have any of the properties described above with regard tomagnetic field sensor 36. Magnetic field sensor 110 may be disposed inany location of tool 108, such as a distal shaft of tool 108.Alternatively, magnetic field sensor 110 may be disposed on member 104.Alternatively, magnetic field sensor 110 may be a stand-alone devicethat may be inserted through a working lumen of member 104. Any of themethods described above with regard to FIGS. 1-4 may be used inconjunction with system 100. After or concurrent with performing suchmethods, tool 108 may be used in performing a procedure such as agastric bypass procedure, either before or after tool 108 detects amagnetic field signature of magnetic device 26. For example, while firstdevice 12 is present in an intestinal lumen (or any other body lumen) ofa subject, second device 102 may be maneuvered in a stomach lumen (orany other body lumen) of a subject. Magnetic field sensor 110 may beutilized in order to detect a magnetic field emitted by magnetic device26. Upon detecting a magnetic field emitted by magnetic device 26, anoperator may be aware of a position of magnetic device 26 relative tosecond device 102. In order to detect the magnetic field emitted bymagnetic device 26, an operator may compare data from magnetic fieldsensor 110 to predetermined qualities of the magnetic field (e.g.,magnitude or direction) and/or may analyze data from magnetic fieldsensor 110 to determine, for example, that a strength or direction ofthe magnetic field measured is changing. Such information may beindicative of a position of magnetic device 26. For example, an operatormay be aware that distal portion 106 is in a portion of a first bodylumen (such as a stomach) that is proximate or adjacent to apredetermined location in a second body lumen (such as a smallintestine) into which first device 12 is inserted (e.g., 150 cm distalof the pylorus). An operator may then advance and/or actuate tool 108 inorder to perform a medical procedure. For example, an operator mayutilize tool 108 in order to grasp a portion of a small bowel that is150 cm from a subject's pylorus. Other suitable tools that may be usedin conjunction with or as an alternative to a grasper include tools usedfor perforating the stomach wall and/or intestinal wall, for affixingthe stomach wall to the intestinal wall, sealing the affixed walls,and/or otherwise providing an anastomosis between the stomach andintestinal walls.

FIG. 6 shows an alternative system 200, which makes use of analternative first device 202. Alternative first device 202 may have anyof the properties of first device 12, described above. First device 202may be used in conjunction with either of second devices 14, 102described above or with an alternative device. First device 202 may havean elongate member or shaft 204, which may have any of the properties ofmember 20, described above. Member 204 may have a distal portion 206,which may have any of the properties of distal portion 22. Distalportion 206 may be have an elongate shape with one or more rounded ends.Distal portion 206 may be shaped approximately like a capsule. Distalportion 206 may make use of a thin wire connection for steering ofdistal portion 206. For example, two-way directional steering may beused. As opposed to using a plastic tube catheter in conjunction withdistal portion 206, a small electrical wire could both tether distalportion 206 and provide length measurement and/or electricity. Such awire could be highly flexible and small in diameter (e.g., a smallerdiameter than a catheter). Distal portion 206 may include a magneticdevice 210, which may have any of the properties of magnetic device 26,described above. Distal portion 206 may have any of the magneticshielding properties of distal portion 22, described above.

Distal portion 206 may also include an illumination portion 212.Illumination portion 212 may be embedded in distal portion 206, may bewithin distal portion 206, may be mounted on distal portion 206, or maybe affixed to distal portion 206 in any other suitable way. Illuminationportion 212 may include, for example, one or more optical fibers, lightemitting diodes (LEDs), or other suitable illumination device.Illumination portion 212 may be configured to emit a steady light and/ora blinking light having any pattern of blinking.

As discussed above, distal portion 36 of second device 14 may includecameras, lenses, or other optical devices. Such cameras, lenses, orother optical devices may be configured to detect light emitted fromillumination portion 212. Light emitted from illumination portion 212may be used in order to identify a portion of a body lumen of interest(e.g., a portion of the small bowel approximately 150 cm from thepylorus), in isolation or in conjunction with magnetic device 210. Forexample, an operator my be able to visualize light emitted fromillumination portion 212 through a wall of a stomach lumen. Illuminationportion 212 may be configured so as to focus emission of light toward awall of a lumen facing second device 14. An operator may also make useof a signal from magnetic field sensor 36.

FIG. 7 shows an exemplary method for performing a medical procedure,which may be used with any of the above method steps, devices, orsystems. As shown in FIG. 7 , a method 200 for performing a medicalprocedure such as a gastric bypass procedure may involve, in step 210,advancing a first device (e.g., first device 12 or first device 202)through a first body lumen, such as a small bowel lumen. First device 12or 202 may be advanced to a predetermined portion of the body lumen,corresponding to a location where an operator desires to manipulate thetissue surrounding the body lumen. As described above, first device 12or 202 may include a magnetic device such as magnetic device 26 or 210,which may be, e.g., a permanent magnet or an electromagnet. In step 220,an operator may advance a second device, such as second device 14 orsecond device 102 through a second body lumen (e.g., a stomach). Asdescribed above, second device 14 or 102 may include a magnetic fieldsensor, such as magnetic field sensor 36 or 110, which may be, e.g., apermanent magnet or an electromagnet. In step 230, an operator mayreceive a signal from a magnetic field sensor 36 or 110. The receivedsignal may be indicative of a measured magnetic field and may includeinformation relating to a direction of a detected magnetic field, amagnitude of a detected magnetic field, or both. In step 240, it may bedetermined whether the signal received in step 230 matches a magneticfield of magnetic device 26 or 210 (such as those described above). Forexample, it may be determined whether a direction of the signal receivedin step 230 matches a predetermined direction or a predeterminedsignature. Additionally or alternatively, whether the received signalmatches a magnetic field of magnetic device 26 and/or 210 may bedetermined by analyzing changes in a reading from a magnetic fieldsensor 36 or 110. For example, a magnetic field of magnetic device 26 or210 may be matched by locating the strongest measured field or bylocating another characteristic feature of magnetic device 26 or 210.

If the received signal does match the magnetic field, then, in step 250,the position of the magnet may be identified in the first body lumen.Based on that information, a predetermined area of interest in the firstbody lumen (or the second body lumen) may be identified. For example, anoperator may identify an area of interest in a tissue wall surroundingthe second body lumen or may identify a portion of the first body lumen(and/or surrounding tissue) that should be manipulated. If, in step 240,the received signal does not match the magnetic field, then step 220 maybe repeated in order to move the second device 14 or 102 to a newportion of the second body lumen and again analyze the magnetic fieldmeasured there.

While principles of the present disclosure are described herein withreference to illustrative examples for particular applications, itshould be understood that the disclosure is not limited thereto. Thosehaving ordinary skill in the art and access to the teachings providedherein will recognize additional modifications, applications, andsubstitution of equivalents all fall within the scope of the examplesdescribed herein. Accordingly, the invention is not to be considered aslimited by the foregoing description.

We claim:
 1. A method for performing a medical procedure, comprising:advancing a first device through a first body lumen to a portion of thefirst body lumen, wherein a distal portion of the first device includesa magnet; advancing a second device through a second body lumen, whereinthe second device includes a magnetic field sensor; receiving a signalfrom the magnetic field sensor, wherein a controller receives thesignal, and wherein the signal is indicative of a magnetic fieldmeasured by the magnetic field sensor; and based on the received signal,joining the portion of the first body lumen to the second body lumen. 2.The method of claim 1, further comprising identifying a location of atissue wall surrounding the first body lumen, wherein the location isproximate to the magnet.
 3. The method of claim 1, wherein the firstbody lumen is a small bowel lumen, and wherein the second body lumen isa gastric lumen.
 4. The method of claim 1, further comprising grasping awall surrounding the first body lumen proximate to the portion of thefirst body lumen.
 5. The method of claim 1, wherein the magnetic fieldhas a direction perpendicular to a tissue wall defining the first bodylumen.
 6. A method for performing a medical procedure, comprising:advancing a first device through a first body lumen, wherein a distalportion of the first device includes a magnet; advancing a second devicethrough a second body lumen, wherein the second device includes amagnetic field sensor; receiving a signal from the magnetic fieldsensor, wherein a controller receives the signal, and wherein the signalis indicative of a magnetic field measured by the magnetic field sensor;and based on the received signal, advancing a medical tool from thesecond body lumen into the first body lumen.
 7. The method of claim 6,further comprising identifying a location of a tissue wall surroundingthe first body lumen, wherein the location is proximate to the magnet.8. The method of claim 6, wherein the first body lumen is a small bowellumen, and wherein the second body lumen is a gastric lumen.
 9. Themethod of claim 6, wherein the magnetic field has a directionperpendicular to a tissue wall defining the first body lumen.
 10. Amethod for performing a medical procedure, comprising: advancing a firstdevice through a first body lumen to a portion of the first body lumen,wherein a distal portion of the first device includes a magnet;advancing a second device through a second body lumen, wherein thesecond device includes a magnetic field sensor; receiving a signal fromthe magnetic field sensor, wherein a controller receives the signal, andwherein the signal is indicative of a magnetic field measured by themagnetic field sensor; and based on the received signal, providing ananastomosis between the portion of the first body lumen and the secondbody lumen.
 11. The method of claim 10, further comprising identifying alocation of a tissue wall surrounding the first body lumen, wherein thelocation is proximate to the magnet.
 12. The method of claim 10, whereinthe first body lumen is a small bowel lumen, and wherein the second bodylumen is a gastric lumen.
 13. The method of claim 10, further comprisinggrasping a wall surrounding the first body lumen proximate to theportion of the first body lumen.
 14. The method of claim 10, wherein thesignal includes information regarding at least one of a direction or amagnitude of the magnetic field.
 15. The method of claim 10, wherein themagnet is a diametrical magnet.
 16. The method of claim 10, wherein thefirst device includes at least one magnetically shielded portion. 17.The method of claim 10, wherein the second device further includes anatraumatic grasper.
 18. The method of claim 10, wherein the distalportion of the first device further includes a light emitting source,and the method further comprises detecting a light emitted by the lightemitting source.
 19. The method of claim 10, further comprising: forminga first hole in a first tissue wall defining the first body lumen;forming a second hole in a second tissue wall defining the second bodylumen; and creating a junction between the first hole in the firsttissue wall and the second hole in the second tissue wall such that thefirst hole is in communication with the second hole.
 20. The method ofclaim 10, wherein the magnetic field has a direction perpendicular to atissue wall defining the first body lumen.